This invention relates to colorants comprising a chromophore having two methine moieties attached to a benzodifuranone backbone, wherein said moieties optionally have at least one poly(oxyalkylene) chain, preferably at least two such chains attached thereto. Such colorants exhibit excellent thermal stability, effective colorations, excellent low extraction rates, and effective lightfastness levels, particularly when incorporated within certain media and/or on the surface of certain substrates, particularly polyesters. The optional poly(oxyalkylene) chains also increase the solubility in different solvents or resins thereby permitting the introduction of such excellent coloring chromophores within diverse media and/or on diverse substrates as well as provides a liquid colorant which facilitates handling. Compositions and articles comprising such colorants are provided as are methods for producing such inventive colorants.
All U.S. patents cited within this specification are hereby incorporated by reference.
There continues to be a need to provide versatile colorants within various applications such that the coloring agent itself exhibits excellent colorations (particularly at low color loadings and due to inherently high quantum absorption efficiency), high thermal stability, effective lightfastness, low extraction (or drastic reduction in possibility of removal therefrom via extraction by solvents or like sources), ease in handling, ability to mix thoroughly with other coloring agents and thus to provide effective different hues and tints within or on target substrates, and acceptable toxicity levels. There has been a need to provide improved colorants meeting this criteria for certain thermoplastic media, such as polyesters, such that the colorants themselves exhibit excellent compatibility therein (for instance in terms of intrinsic viscosity loss and the other characteristics desired for such plastics as noted above). In particular, such characteristics for polyesters are desired for colorants that absorb, for example, though not necessarily, within the red portion of the visible spectrum. Other hues are available as well for such a desired, high-performing polyester plastic colorant, including blue, yellow, orange, and the like, all dependent on the presence of certain coupling or modifying moieties present on the chromophore backbone itself. It is believed and, as noted above, has been determined that such desirable polyester plastic colorations with the characteristics noted above are possible through the addition of certain pendant groups to the chromophore backbone which do not act as couplers or color modifiers [such as, for example poly(oxyalkylene) groups] and thus any chromophore (and resultant hue or tint) may be utilized with the desired benzodifuranone bismethine chromophore itself.
Previous coloring agents for such end-uses have included pigments, dyes, or dyestuffs, with each having its own drawback, be it an extraction problem from the finished article, a handling problem during manufacturing due to solid dust particles, a staining problem, due to the difficulty associated with cleaning such coloring agents from manufacturing machinery after colored plastic production, and other like issues. As a result, there is a clear desire to provide easier to handle, less extractable, easy-to-clean, etc., coloring agents for introduction within thermoplastic articles to provide decorative, aesthetic, and other like effects. However, the chromophores present within such dyes, pigments, and the like, are highly desired for the hues and shades they provide within the ultimate thermoplastic articles themselves. Facilitating the introduction of such chromophores within such formulations is thus a highly desired target within the colored thermoplastic industry, whether it be in terms of handling, extraction, cleaning, or the like.
Attempts to meet this desire have included the introduction of certain standard types of polymeric colorants within plastics (be they thermoplastics or thermoset types). These colorants are primarily poly(oxyalkylenated) compounds, such as triphenylmethanes, methines, and the like (i.e., those found within U.S. Pat. No. 4,992,204, to Kluger et al.). Some of these colorants exhibit certain problems during incorporation into thermosets and thermoplastics. In thermoplastic compositions such as polyesters, many of these previously disclosed compositions are not stable at the polyester processing temperatures. As a result, the colorations provided by such polymeric colorants may be reduced in strength or changed in shade under such circumstances. Other types of colorants have been discussed within the prior art, such as azos and bisazos, but the specific colorations provided by such compounds are limited to certain hues and their utilization within polyesters is suspect from a number of perspectives (such as thermal stability, and the like). There is thus a desire to introduce new types of colorants comprising different types of chromophores for the purpose of providing new, effective, versatile colorants for such myriad end-uses as noted above and that exhibit excellent colorations, extraction, thermal stability, mixing with other coloring agents, and low toxicity, at least.
A certain class of colorants, namely benzodifuranone derivatives, exhibit excellent colorations and have been utilized within different applications, most prominently within inks, such as in U.S. Pat. No. 5,665,150 to Schwarz, and U.S. Pat. No. 5,779,778 to Gregory et al. and as disperse dyes for polyester, such as in J. Soc. Dyers Colour. 110, 1994, p, 178. The chromophores disclosed in this art are significantly structurally and thus electronically different from the inventive chromophores disclosed herein, exhibiting a substituted phenyl group attached directly to the benzodifuranone core structure, and thus cannot be classified as methines. There has also been some discussion of introducing isatin-based benzodifuranones within plastics as disclosed within published PCT Application WO00/24736 to Ciba Specialty Chemicals. Such compounds are limited to non-polymeric species and, again, require the presence of isatin as a substituent (and thus a heterocyclic pendant group attached to the double bond between such an isatin adduct and the backbone benzodifuranone compound). Apparently, such compounds provide effective colorations within plastics; however, there is no discussion of the handling issues, mixing capabilities with other colorants, migratory properties, lightfastness, or other concerns with colorants for plastics. Furthermore, the reaction with isatin is rather costly and the yield is suspect thus increasing the potential costs to the end-user and/or the consumer. A new type of benzodifuranone colorant for plastic applications (at least) is thus desirable, primarily due to the potential colorations provided by such base chromophores. Furthermore, simplified methods of producing such benzodifuranone derivatives are also desired such that the end colorant can be tailored in its constitution to any end-use application through the presence of poly(oxyalkylene) groups thereon. Such an option would thus provide much-needed versatility for such desirable coloring agents within various media (including the aforementioned plastics, liquids, foams, and the like). To date, there have been no teachings or fair suggestions of such a highly desirable, specific potentially polymeric benzodifuranone derivative colorant within the pertinent prior art or within the colorant industry itself.
It is thus an object of the invention to provide novel thermally stable polymeric colorants for utilization within thermoplastic and thermoset articles based on bismethine benzodifuranone backbone structures. Yet another object of this invention is to provide excellent colorations within liquid compositions (such as inks, and the like) through the utilization of the same bismethine benzodifuranone-type compounds as noted above. The features of this new chromophore are exceptionally high color strength and exceptionally high heat stability. In the liquid embodiments demonstrated herein, the colorant exhibits low extraction from thermoplastics such as polyester, little effect on the molecular weight (intrinsic viscosity) of polyester when incorporated at high color loading, low toxicity and ease of handling (homogeneous liquid). It is a further object of this invention to provide new solid dye compositions suitable for the coloration of textile materials, in particular advantageous in the dyeing of hydrophobic fibers such as polyester.
It is to be understood that the term alkyl as used throughout is intended to encompass any straight or branched alkyl moiety, having anywhere from 1 to 30 carbons therein; the same chain length applies to the term xe2x80x9calkoxyxe2x80x9d as well. Also, the terms substituted phenyl and substituted polyphenyl are intended to encompass any phenyl system having any type of pendant group attached thereto, including, without limitation, alkyl groups, alkylene groups, alcohol groups, ether groups, ester groups, amine groups, nitro groups, amide groups, hydroxyls, thiols, and the like. Phenyl is basically an unsubstituted ring system (and thus includes hydrogens only as pendant groups).
The present invention preferably encompasses colorants conforming to the structure of Formula (I) 
wherein Y is selected from the group consisting of hydrogen, alkyl, halogen, alkenyl, hydroxy, and alkoxy; X is selected from the group consisting of any atom that provides a heterocyclic system for the cyclic ring; B is selected from the group consisting of alkenyl, phenyl, polyphenyl, substituted phenyl, substituted polyphenyl, alkenyl-Q-A, phenyl-Q-A, polyphenyl-Q-A, substituted phenyl-Q-A, and substituted polyphenyl-Q-A, wherein Q is selected from the group consisting of N, O, S, SO2, SO3, CO2, SO2N, alkyl, and alkoxy, and A either conforms to the structure of Formula (VII)
[polyoxyalkylene constituent]zRxe2x80x2xe2x80x83xe2x80x83(VII)
wherein z is 1 or 2; polyoxyalkylene constituent is selected from the group consisting of at least three monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof; and Rxe2x80x2 is selected from the group consisting of hydrogen, C1-20 alkyl, C1-20 alkylester, halo, hydroxyl, hydrogen, thio, cyano, sulfonyl, sulfo, sulfato, aryl, nitro, carboxyl, C1-20 alkoxy, amino, C1-20 alkylamino, acrylamino, C1-20 alkylthio, C1-20 C1-20 alkylsufonyl, C1-20 alkylphenyl, phosphonyl, C1-20 alkylphosphonyl, C1-20 alkoxycarbonyl, phenylthio; or conforms to the structure E, wherein E is an unsaturated heterocylic residue selected from the group consisting of furyl, thienyl, pyrrolyl, pyridyl, pyranyl, thiazolyl, oxazolyl, pyrazolyl, imidazolyl, thiadiazolyl, and s-triazoyl. Alternatively, E represents a saturated heterocyclic residue selected from the group consisting of tetrahydrofuryl, tetrahydrothienyl, pyrrolidyl, piperidyl, tetrahydropyranyl, piperazinyl, morphonyl, and hexahydroazepinyl. Also, E represents a hetrocyclic residue condensed with benzene rings such as benzofurnayl, benzothienyl, indolyl, benzoxazolyl, benzimidazolyl, and benzothiazolyl, as well as a phenyl substituted with any or all of R1, R2, R3, R4, and R5. Preferably, Y is hydrogen, X is O, R1, R2, R3, R4, R5, and Rxe2x80x2 are hydrogen, with preferably, though not necessarily, at least one of R1, R2, R3, R4, and R5 being Q-A; polyoxyalkylene constituent is ethylene oxide (EO), propylene oxide (PO), or any combinations thereof; and Q is N. Preferably, B is a moiety that exhibits conjugation when incorporated and present within the structure (I) in order to provide desired colorations, as well as a moiety including the above-defined Q-A group; more thorough descriptions of such groups are presented below.
More specifically, and preferably (though in a non-limiting capacity), the inventive benzodifuranone bismethine colorant conforms to the structure of (II) 
wherein X and Y are defined as for (I), above, and wherein R1, R2, R3, R4, and R5 are the same or different and are selected from the group consisting of hydrogen, C1-20 alkyl, C1-20 alkylester, halo, hydroxyl, hydrogen, thio, cyano, sulfonyl, sulfo, sulfato, aryl, nitro, carboxyl, C1-20 alkoxy, amino, C1-20 alkylamino, acrylamino, C1-20 alkylthio, C1-20 C1-20 alkylsufonyl, C1-20 alkylphenyl, phosphonyl, C1-20 alkylphosphonyl, C1-20 alkoxycarbonyl, phenylthio, and Q-A, wherein Q is selected from the group consisting of N, O, S, SO2, SO3, CO2, SO2N, alkyl, and alkoxy, and A either conforms to the structure of Formula (VII)
[polyoxyalkylene constituent]zRxe2x80x2xe2x80x83xe2x80x83(VII)
wherein z is 1 or 2; polyoxyalkylene constituent is selected from the group consisting of at least three monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, and Rxe2x80x2 is selected from the group consisting of hydrogen, C1-20 alkyl, C1-20 alkylester, halo, hydroxyl, hydrogen, thio, cyano, sulfonyl, sulfo, sulfato, aryl, nitro, carboxyl, C1-20 alkoxy, amino, C1-20 alkylamino, acrylamino, C1-20 alkylthio, C1-20 C1-20 alkylsufonyl, C1-20 alkylphenyl, phosphonyl, C1-20 alkylphosphonyl, C1-20 alkoxycarbonyl, and phenylthio; or conforms to the structure of E, wherein E is an unsaturated heterocylic residue selected from the group consisting of furyl, thienyl, pyrrolyl, pyridyl, pyranyl, thiazolyl, oxazolyl, pyrazolyl, imidazolyl, thiadiazolyl, and s-triazoyl. Alternatively, E represents a saturated heterocyclic residue selected from the group consisting of tetrahydrofuryl, tetrahydrothienyl, pyrrolidyl, piperidyl, tetrahydropyranyl, piperazinyl, morphonyl, and hexahydroazepinyl. Also, E represents a heterocyclic residue condensed with benzene rings such as benzofurnayl, benzothienyl, indolyl, benzoxazolyl, benzimidazolyl, and benzothiazolyl, as well as a phenyl substituted with any or all of R1, R2, R3, R4, and R5. Preferably, R1, R2, R3, R4, R5, and Rxe2x80x2 are hydrogen, with preferably though not necessarily, at least one of R1, R2, R3, R4, and R5 being Q-A; polyoxyalkylene constituent is ethylene oxide (EO), propylene oxide (PO), or any combinations thereof; and Q is N.
Further preferred inventive colorants conform to the following structures (III), (IV), (V), and (VI): 
wherein A is represented by the Formula (VII)
[polyoxyalkylene constituent]zRxe2x80x2xe2x80x83xe2x80x83(VII)
wherein z is 1 or 2; polyoxyalkylene constituent is selected from the group consisting of at least three monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof; and Rxe2x80x2 is selected from the group consisting of hydrogen, C1-20 alkoxy, C1-20 alkyl, and C1-20 esters. 
wherein A is represented by the Formula (VII)
[polyoxyalkylene constituent]zRxe2x80x2xe2x80x83xe2x80x83(VII)
wherein z is 1 or 2; polyoxyalkylene constituent is selected from the group consisting of at least three monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, and Rxe2x80x2 is selected from the group consisting of hydrogen, C1-20 alkoxy, C1-20 alkyl, and C1-20 esters. 
wherein A is represented by the Formula (VII)
[polyoxyalkylene constituent]zRxe2x80x2xe2x80x83xe2x80x83(VII)
wherein z is 1 or 2; polyoxyalkylene constituent is selected from the group consisting of at least three monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, and Rxe2x80x2 is selected from the group consisting of hydrogen, C1-20 alkoxy, C1-20 alkyl, and C1-20 esters. 
wherein A is represented by the Formula (VII)
[polyoxyalkylene constituent]zRxe2x80x2xe2x80x83xe2x80x83(VII)
wherein z is 1 or 2; polyoxyalkylene constituent is selected from the group consisting of at least three monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof, monomers of at least one C2-20 alkyleneoxy group, glydicol, glycidyl, or mixtures thereof; and Rxe2x80x2 is selected from the group consisting of hydrogen, C1-20 alkoxy, C1-20 alkyl, and C1-20 esters.
Compositions comprising such compounds of (I)-(VI) are also encompassed within this invention, particularly those comprising such compounds and other coloring agents, ultraviolet absorbers, bluing agents, or mixtures thereof, as liquids or as pellets for further introduction within desired molten thermoplastic or thermoset formulations (or precursor formulations). Methods of making such compositions, particularly thermoplastics, comprising such compounds of (I)-(VI) are also contemplated within this invention.
The term xe2x80x9cthermoplasticxe2x80x9d is intended to encompass any synthetic polymeric material that exhibits a modification in physical state from solid to liquid upon exposure to sufficiently high temperatures. Most notable of the preferred thermoplastic types of materials are polyolefins (i.e., polypropylene, polyethylene, and the like), polyester (i.e., polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, and the like), polyamides (i.e., nylon-1,1, nylon-1,2, nylon-6 or nylon-6,6), polystyrenes, polycarbonates, polyvinyl halides (i.e., polyvinyl chloride and polyvinyl difluoride, as merely examples), and the like. Preferred thermoplastics within this invention are polyesters, and most preferred is polyethylene terephthalate.
Such thermoplastic articles include bottles, storage containers, sheets, films, fibers, plaques, hoses, tubes, syringes, and the like. Included within this list would be polyester, polystyrene and other like resinous materials in sheet form which are present within windows for strength and resiliency functions. In such an instance, the inventive colorant compounds would provide or contribute to excellent colorations to such thermoplastic articles for decorative, aesthetic, and/or protective (such as ultraviolet or infrared protection) purposes. Basically, the possible uses for such a low-migratory, thermally stable colorant for such items as thermoplastics (particularly polyesters such as transparent polyethylene terephthalate) is voluminous and cannot easily be enveloped. Other possible end-uses, however, would include within solvent systems, printing inks, within and on textiles (either on or within textiles, fibers, or fabrics), within display devices such as liquid crystal displays, and the like.
The inventive colorant compounds may be added in any amount to such thermoplastics up to their saturation limits therein. Preferably, the amount is between about 0.00001 ppm to about 25,000 ppm per total amount of resin; more preferably from about 0.001 to about 15,000 ppm; still more preferably from about 0.1 to about 5,000 ppm; and most preferably from about 100 to about 2,500 ppm. Of course, the more colorant present, the darker the shade therein. When mixed with other colorants within the target thermoplastic, the same amounts would be preferred with the saturation limit dependent upon the amount of any extra colorants therein.
The term xe2x80x9cthermosetxe2x80x9d or xe2x80x9cthermosetsxe2x80x9d encompasses a polymeric solid which, upon exposure to sufficient heat or in the presence of a sufficient amount of catalyst, configures itself into a pre-determined shape. Such formulations encompassed within this term includes polyurethanes, and the like. Thus, foams, sheets, articles, coverings, and the like, are all envisioned within this definition.
The inventive colorant compounds may be added in any amount to such thermosets up to their saturation limits therein. Preferably, the amount is between about 0.00001 ppm to about 25,000 ppm per total amount of resin; more preferably from about 0.001 to about 15,000 ppm; still more preferably from about 0.1 to about 5,000 ppm; and most preferably from about 100 to about 2,500 ppm. Of course, the more colorant present, the darker the shade therein. When mixed with other colorants within the target thermoset, the same amounts would be preferred with the saturation limit dependent upon the amount of any extra colorants therein.
Other types of articles contemplated within this invention for the inventive colorant compounds include, again without limitation, thermoplastic articles, such as films, sheets, bottles, containers, vials, and the like. Other colorants may be added to or incorporated therein with such inventive colorant compounds to produce different hues and tints, again for aesthetic, decorative, and/or protective purposes. Ultraviolet absorbers may also be introduced, incorporated, and the like, in order to protect the article or, if in container for, the contents therein.
Such thermoplastic and/or thermoset colorants (and other additives) are typically added to such compositions during the injection molding (or other type of molding, such as blow molding), thereof, including, and without limitation, by mixing the liquid absorber with resin pellets and melting the entire coated pellets, or through a masterbatch melting step while the resin and absorber are pre-mixed and incorporated together in pellet form. Such plastics include, again without limitation, polyolefins, polyesters, polyamides, polyurethanes, polycarbonates, and other well known resins, such as those disclosed within U.S. Pat. No. 4,640,690, to Baumgartner et al., and U.S. Pat. No. 4,507,407, to Kluger et al. under the term xe2x80x9cthermoplasticsxe2x80x9d and/or xe2x80x9cthermosetsxe2x80x9d. Generally, such plastics, including the colorant, UV absorber, and other potential additives, are formed through any number of various extrusion, etc., techniques, such as those disclosed in the aforementioned U.S. patents. Preferred thermoplastics are polyesters, such as, in one non-limiting embodiment, polyethylene terephthalate. xe2x80x9cPlastic packagingxe2x80x9d thus encompasses containers, sheets, blister packages, and the like, utilized for storage purposes and which include the plastics in any combination as noted above.
The term xe2x80x9cpure, undiluted statexe2x80x9d as used in conjunction with the inventive colorant compounds indicates that the compounds themselves without any additives are liquid at room temperature. Thus, there is no need to add solvents, viscosity modifiers, and other like additives to the compounds to effectuate such a desirable physical state.
The presence of surfactants, solvents, and the like, may be utilized to alter the solubility, coloring characteristics, and the like, of the ultimate inventive benzodifuranone bismethine colorant [whether poly(oxyalkylenated) or not] which would be understood and appreciated by the ordinarily skilled artisan within this particular art. It is also understood that solid versions of such inventive colorants (e.g., dyestuffs, pigments, and the like) could be dispersed within liquid media to provide stable dispersions thereof for further utilization.
Preferably, the colorant compounds (I)-(VI) are liquid in nature at ambient temperature and pressure and at substantial purity; however, pasty, waxy, or crystalline colorants are also encompassed within this invention. In order to effectuate coloring of substrates and media, any other standard colorant additives, such as resins, preservatives, surfactants, solvents, antistatic compounds, antioxidants, antimicrobials, and the like, may also be utilized within the inventive colorant compound compositions or methods.
For liquid composition applications, the amount present should range from about 0.00001 ppm to about 30,000 ppm of the total solvent present; preferably, from about 0.001 to about 15,000 ppm; still more preferably from about 0.1 to about 5,000 ppm; and most preferably from about 100 to about 2,500 ppm. Of course, the more colorant present, the darker the shade therein. When mixed with other colorants within the target solvent, the same amounts would be preferred.
The specific formulations below, as well as the following exemplified methods of producing such and methods of coloring using such are thus indicative of the preferred embodiments of this invention (all of the initial aniline derivatives and aldehyde derivatives were produced in accordance with the method taught within U.S. Pat. No. 4,594,454 to Moore et al.):
Colorant Formation